private void populateInputVariableComboBox() {
    inputVariableComboBox.setEnabled(false);

    inputVariableComboBox.setDecomposition(attribute.getDecomposition());

    if (inputVariableComboBox.getItemCount() > 0) {
      inputVariableComboBox.setEnabled(true);
      inputVariableQueryButton.setEnabled(true);
    } else {
      inputVariableComboBox.setEnabled(false);
      inputVariableQueryButton.setEnabled(false);
    }
  }
  public void setExtendedAttribute(ExtendedAttribute attribute) {
    this.attribute = attribute;
    populateInputVariableComboBox();

    String value = URLDecoder.decode(attribute.getValue());
    if (value.startsWith("${")) {
      value = value.substring(2);
      value = value.substring(0, value.length() - 1);
      useXQuery.setSelected(true);
      xQueryEditor.setValidating(true);
    } else {
      useXQuery.setSelected(false);
      xQueryEditor.setValidating(false);
    }

    _text = value;
    xQueryEditor.setText(value);
  }